The purpose of the Molecular and Cell Biology Core is to consistently provide high quality biochemical and cellular resources to the Sub-Projects. Primary trigeminal ganglion cultures will be derived from both rat and baboon trigeminal ganglia. These primary cultures will be used to study opioid receptor-mediated signaling (subproject #1), and the effects of integrin receptor activation (subproject #2). This Core facilitates these research programs by ensuring quality control, by achieving economies of scale and by permiting project scientists to concentrate on experiments rather than preparation and maintenance of cultures. Quality control issues are particulady important in primary neuronal cell cultures which must be optimized with respect to reagents and culture conditions in order to achieve high quality and consistent results. Our quality control program includes assessment of functional (i.e, central repository and analysis of all control data (eg., PGE2-evoked cAMP accumulation) from all sub-projects) and immunological (e.g., immunostaining for marker proteins) measures to ensure consistency of culture conditions across Sub-Projects and over time. This Core will also perform various radioimmunoassays (RIA) for each of the subprojects. Release of the neuropeptides, substance P (SP) and calcitonin gene-related peptide (CGRP) will be used as a readout for opioid receptor signaling in all four subprojects, Opioid receptor-mediated inhibition of cAMP accumulation will also be a common read-out for opioid receptor signaling (subprojects 1, 2, and 3). Therefore, RIAs for SP, CGRP and cAMP will be done by the Core on a routine basis. These services are necessary to conduct the experiments proposed in the subprojects in an efficient way and guarantee the necessary quality control and consistency across the program project. In addition to performing a service, starting in year 3, the Core will be responsible for the development and implementation of transfection protocols for expression of foreign DNA in primary rat and baboon TG ganglia cultures. The goal will be to provide suitably transfected cultures with a given signaling molecule gene of interest (e.g., dominant negative strategies) to the individual subprojects in order to delineate specific signaling molecules involved in opioid receptor function as well as real time measures in single cells. Overall, the Core is designed to maximize efficient use of resources to generate consistent high quality data, and to prepare new technologies for the evolving needs of the Sub-Projects.